Sam Bradford runs through the play calls on the practice field, getting his protections straight.

“Rise and Grind” has become the unofficial anthem of the self-motivated athlete — the mantra spoken as he wills himself forward through pain and frustration toward a goal of his choosing. Away from the lights, the promise of glory, or a coach’s whistle, there has to be something in his core driving him to succeed, and sometimes it just needs a few words to be voiced.

“It’s great to get out here, get to know the guys, and get to know the offense and everything we’re going to have to be learning,” said first-year pro Greg Salas. “You can see the difference with the leadership and the maturity of the men out here.”

The leadership comes from three players who are nearly impossible to out-study or out-work: Ron Bartell, James Laurinaitis, and Sam Bradford. This trio got an assist in maturity from two former Rams greats who are now entering their second act in the NFL, Corey Chavous and Torry Holt. But, especially on offense, this was Bradford’s show from the beginning.

He was in complete charge as the offense took the field and ran through page after page of their new playbook. “I feel pretty good with it,” Bradford said after the first of four scheduled workouts this week. “I spent quite a bit of time (studying) since I got (the playbook). Now it’s just a matter of getting (repetitions). You can look at something on paper all day and it will make sense, but until you get on the field and actually run through it a couple of times, you don’t actually know how it will play out and you don’t know what the timing will be. So the more you work on it, the more you get the timing down.”

For the last two years, the Rams young and old have been herded up and down the practice field by the relentless energy of coach Spagnuolo and his staff. They bark, they goad, and they take time to instruct, but as a rule they never stand still. And from the sound of things, that energy has been preserved, to a point.

“We’re obviously competing, but we’re not going extremely hard because of the fact that we want to keep everyone healthy,” says Bradford. “We’d hate to have an injury while we’re doing this.”

There’s impressive depth at this camp, particularly at the offensive skill positions that are suddenly full to overflowing. Last year’s complete depth chart at tight end is here: Fells, Bajema, Hoomanawanui and Onobun, and they are joined by the rookie Lance Kendricks. While only four wideouts started the week: the rookie Salas along with Donnie Avery, Danny Amendola and Brandon Gibson, at least three more including Danario Alexander, Laurent Robinson and Austin Pettis will be joining the group as soon as today.

There’s camaraderie in numbers, but there’s also competition, knowing that only so many spots will be available when and if the season starts again. You can almost hear the unspoken counterpart to “rise and grind” … “don’t get left behind.”